Why is having a license plate even relevant here? Most traffic enforcement is done when an officer sees something happen.
Don't victim blame.
If you cannot control yourself enough to slow down around people, you need to get out of the driver's seat. If you cannot stop before a potential crash, you were going too fast. 100% of the time. It literally does not matter if someone jumps in front of you. If you're going to choose the statistically most violent mode of transportation by multiple orders of magnitude, that is your responsibility.
As for license plates, I'd like both cars and bikes to obey the law. The only way I see that happening is cameras and scanners. For that to stop bikes requires the bikes to also have plates.
The license plate issue is that cities can, and are, adding more and more license plate scanners to catch cars. Those won't work for bicycles and ebikes (who drive like cyclists) unless they require license plates on bikes/ebikes and enforce. Yes, and enforce more on cars too.
Also, you can ask Google AI for more sources and info using this prompt:
japan when does a bike require a license plate?And I don't need to ask AI, I used an e-bike (without a licence plate) last week in Tokyo.
> I used an e-bike (without a licence plate) last week in Tokyo.
Did you (1) need to pedal to get assistance, or (2) could you get power with a throttle button only? If #2, then you were breaking the law. It seems like police are not yet enforcing. In neighborhoods with a lot of "night life", I see this often with host-looking dudes. I expect 6-12 months after the law is activated, police will begin to crack down. (This is a pretty normal pattern when introducing new traffics laws in Japan.)